Double-cropping Winter Wheat and Soybean Improves Net Returns in the Eastern Great Plains

Abstract

In the eastern Great Plains, winter wheat (Triticum aestivum L.) and different soybean [Glycine max(L.) Merr.] maturity groups (MG) are grown in various cropping systems to diversify crop production. A 10-year field study was conducted in southeastern Kansas to evaluate effects of multi-cropping systems on grain yield and net economic returns. Cropping systems evaluated were: (i) annual double-cropping of wheat and soybean (MG IV); (ii) four 2-year rotations of wheat-soybean double-cropped followed by full-season soybean the next year, where the same soybean MG (I, III, IV, and V) was grown both years; and (iii) a 3-year rotation of wheat, wheat, and full-season (MG V) soybean. On average, wheat yields ranged from 51 bu/acre following early MG I soybean in the 2-year double-crop rotation to 36 bu/acre following MG IV soybean in the annual double-cropping system. Wheat yield differences were primarily determined by planting date. Full-season (MG V) soybean yields were highest (35 bu/acre) following two years of wheat in the 3-year rotation. Double-crop soybean yields in the annual double-cropping system averaged 26 bu/acre for MG IV. Full-season and double-crop soybean yields in the 2-year double-crop rotation system were significantly greater for traditional MGs (III, IV, and V) than MG I. Net economic returns averaged $101/acre for annual double-cropping, which was $10 to $25/acre higher than 2-year systems with MGs III, IV, and V; whereas, net returns were lowest for the 3-year rotation ($51/acre) and for the 2-year system with MG I soybean ($44/acre).